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1.
Vibrio is a recognized fast‐growing bacterial genus, which is considered to be attractive for the development of next‐generation biotechnological workhorses. Here, three Vibrio strains FA1, FA2, and FA3, capable of growing rapidly in cost‐effective media, are isolated and systematically evaluated. Genome sequencing and comparative genomic analyses are performed to reveal the underlying genetic differences between the strains and estimate their biotechnological potential. Studies of their phylogenetic tree, colinear visualization, and orthology uncover some difference in the gene content related to cell growth of the four Vibrio strains FA1, FA2, FA3, and ATCC 14048, which may explain growth superiority of the isolated strains. It is noted that there are more copies of several genes related to the DNA replication in the FA2 genome than in the other compared Vibrio strains. Furthermore, the genes responsible for amino synthesis are found, such as asD, within strains FA1 and FA2. Gene cluster cadABC, which relates to cell adaptation at acidic pH, only exists in strains FA1, FA2, and FA3. Finally, the wide spectra of substrates and genetic operability of these three isolated Vibrio strains are initially verified. This study provides excellent candidates for the development of next‐generation fast‐growing microbial workhorses, which may be very useful in synthetic biology. 相似文献
2.
Laurent X Nouvel Tiago Dos Vultos Eric Kassa-Kelembho Jean Rauzier Brigitte Gicquel 《BMC microbiology》2007,7(1):39
Background
Previous studies have suggested that variations in DNA repair genes of W-Beijing strains may have led to transient mutator phenotypes which in turn may have contributed to host adaptation of this strain family. Single nucleotide polymorphism (SNP) in the DNA repair gene mutT1 was identified in MDR-prone strains from the Central African Republic. A Mycobacteriumtuberculosis H37Rv mutant inactivated in two DNA repair genes, namely ada/alkA and ogt, was shown to display a hypermutator phenotype. We then looked for polymorphisms in these genes in Central African Republic strains (CAR). 相似文献3.
Jesús Aranda Margarita Poza Belén G Pardo Soraya Rumbo Carlos Rumbo José R Parreira Patricia Rodríguez-Velo Germán Bou 《BMC microbiology》2010,10(1):279
Background
Acinetobacter baumannii is a multidrug-resistant bacterium responsible for nosocomial infections in hospitals worldwide. Study of mutant phenotypes is fundamental for understanding gene function. The methodologies developed to inactivate A. baumannii genes are complicated and time-consuming; sometimes result in unstable mutants, and do not enable construction of double (or more) gene knockout mutant strains of A. baumannii. 相似文献4.
Background
There are four widely used experimental strains of N. gonorrhoeae, one of which has been sequenced and used as the basis for the construction of a multi-strain, mutli-species pan-neisserial microarray. Although the N. gonorrhoeae population structure is thought to be less diverse than N. meningitidis, there are some recognized gene-complement differences between strains, including the 59 genes of the Gonococcal Genetic Island. In this study we have investigated the three experimental strains that have not been sequenced to determine the extent and nature of their similarities and differences. 相似文献5.
Background
The induction of metalloprotease encoded by empA in Vibrio anguillarum occurs at high cell density in salmon intestinal mucus. Previously we have shown that there are significant differences in empA expression in two strains of V. anguillarum, M93Sm and NB10. It is hypothesized that differences in empA regulation are due to differences in binding of regulatory elements. 相似文献6.
Background
Mycoplasma hyopneumoniae is the primary cause of enzootic pneumonia in pigs. Although vaccination is an important control tool, the results observed under field conditions are variable. This may be due to antigenic differences between the strains circulating in pig herds and the vaccine strain. This study compared the protective efficacy of four bacterins against challenge infection with a highly virulent field strain of M. hyopneumoniae. 相似文献7.
Wilfried Rozhon Elena Petutschnig Mamoona Khan David K Summers Brigitte Poppenberger 《BMC microbiology》2010,10(1):56
Background
Rahnella is a widely distributed genus belonging to the Enterobacteriaceae and frequently present on vegetables. Although Rahnella has interesting agro-economical and industrial properties and several strains possess antibiotic resistances and toxin genes which might spread within microbial communities, little is known about plasmids of this genus. Thus, we isolated a number of Rahnella strains and investigated their complements of small plasmids. 相似文献8.
Background
Cell-free protein synthesis is not only a rapid and high throughput technology to obtain proteins from their genes, but also provides an in vitro platform to study protein translation and folding. A detailed comparison of in vitro protein synthesis in different cell-free systems may provide insights to their biological differences and guidelines for their applications. 相似文献9.
Background
Alpha (α)-hemolysin is a pore forming cytolysin and serves as a virulence factor in intestinal and extraintestinal pathogenic strains of E. coli. It was suggested that the genes encoding α-hemolysin (hlyCABD) which can be found on the chromosome and plasmid, were acquired through horizontal gene transfer. Plasmid-encoded α-hly is associated with certain enterotoxigenic (ETEC), shigatoxigenic (STEC) and enteropathogenic E. coli (EPEC) strains. In uropathogenic E. coli (UPEC), the α-hly genes are located on chromosomal pathogenicity islands. Previous work suggested that plasmid and chromosomally encoded α-hly may have evolved independently. This was explored in our study. 相似文献10.
Natsumi Okada Shigeaki Matsuda Junko Matsuyama Kwon-Sam Park Calvin de los Reyes Kazuhiro Kogure Takeshi Honda Tetsuya Iida 《BMC microbiology》2010,10(1):302
Background
Vibrios, which include more than 100 species, are ubiquitous in marine and estuarine environments, and several of them e.g. Vibrio cholerae, V. parahaemolyticus, V. vulnificus and V. mimicus, are pathogens for humans. Pathogenic V. parahaemolyticus strains possess two sets of genes for type III secretion system (T3SS), T3SS1 and T3SS2. The latter are critical for virulence of the organism and be classified into two distinct phylogroups, T3SS2α and T3SS2β, which are reportedly also found in pathogenic V. cholerae non-O1/non-O139 serogroup strains. However, whether T3SS2-related genes are present in other Vibrio species remains unclear. 相似文献11.
Saira Ahmad Lyman Hunter Aiping Qin Barbara J Mann Monique L van Hoek 《BMC microbiology》2010,10(1):123
Background
Macrolide antibiotics are commonly administered for bacterial respiratory illnesses. Azithromycin (Az) is especially noted for extremely high intracellular concentrations achieved within macrophages which is far greater than the serum concentration. Clinical strains of Type B Francisella (F.) tularensis have been reported to be resistant to Az, however our laboratory Francisella strains were found to be sensitive. We hypothesized that different strains/species of Francisella (including Type A) may have different susceptibilities to Az, a widely used and well-tolerated antibiotic. 相似文献12.
Background
The genus Pseudomonas comprises more than 100 species of environmental, clinical, agricultural, and biotechnological interest. Although, the recommended method for discriminating bacterial species is DNA-DNA hybridisation, alternative techniques based on multigenic sequence analysis are becoming a common practice in bacterial species discrimination studies. Since there is not a general criterion for determining which genes are more useful for species resolution; the number of strains and genes analysed is increasing continuously. As a result, sequences of different genes are dispersed throughout several databases. This sequence information needs to be collected in a common database, in order to be useful for future identification-based projects. 相似文献13.
Maha Bouzid Kevin M Tyler Richard Christen Rachel M Chalmers Kristin Elwin Paul R Hunter 《BMC microbiology》2010,10(1):213
Background
Cryptosporidium is a protozoan parasite that causes diarrheal illness in a wide range of hosts including humans. Two species, C. parvum and C. hominis are of primary public health relevance. Genome sequences of these two species are available and show only 3-5% sequence divergence. We investigated this sequence variability, which could correspond either to sequence gaps in the published genome sequences or to the presence of species-specific genes. Comparative genomic tools were used to identify putative species-specific genes and a subset of these genes was tested by PCR in a collection of Cryptosporidium clinical isolates and reference strains. 相似文献14.
T. Yasuda M. Waki K. Kuroda D. Hanajima Y. Fukumoto T. Yamagishi Y. Suwa K. Suzuki 《Journal of applied microbiology》2013,114(3):746-761
Aims
To investigate community shifts of amoA‐encoding archaea (AEA) and ammonia‐oxidizing bacteria (AOB) in biofilter under nitrogen accumulation process.Methods and Results
A laboratory‐scale rockwool biofilter with an irrigated water circulation system was operated for 436 days with ammonia loading rates of 49–63 NH3 g m?3 day?1. The AEA and AOB communities were investigated by denaturing gradient gel electrophoresis, sequencing and real‐time PCR analysis based on amoA genes. The results indicated that changes in abundance and community compositions occurred in a different manner between archaeal and bacterial amoA during the operation. However, both microbial community structures mainly varied when free ammonia (FA) concentrations in circulation water were increasing, which caused a temporal decline in reactor performance. Dominant amoA sequences after this transition were related to Thaumarchaeotal Group I.1b, Nitrosomonas europaea lineages and one subcluster within Nitrosospira sp. cluster 3, for archaea and bacteria, respectively.Conclusions
The specific FA in circulation water seems to be the important factor, which relates to the AOB and AEA community shifts in the biofilter besides ammonium and pH.Significance and Impact of the Study
One of the key factors for regulating AEA and AOB communities was proposed that is useful for optimizing biofiltration technology. 相似文献15.
Nanyan?Noreen Wei?Yeng?Hooi Ali?Baradaran Mohamad?Rosfarizan Chin?Chin?Sieo Md?Illias?Rosli Khatijah?Yusoff Abdul?Rahim?Raha
Background
Many plasmid-harbouring strains of Lactococcus lactis have been isolated from milk and other sources. Plasmids of Lactococcus have been shown to harbour antibiotic resistance genes and those that express some important proteins. The generally regarded as safe (GRAS) status of L. lactis also makes it an attractive host for the production of proteins that are beneficial in numerous applications such as the production of biopharmaceutical and nutraceutical. In the present work, strains of L. lactis were isolated from cow's milk, plasmids were isolated and characterised and one of the strains was identified as a potential new lactococcal host for the expression of heterologous proteins. 相似文献16.
Zhu-Mei He Michael S Price Gregory R OBrian D Ryan Georgianna Gary A Payne 《BMC microbiology》2007,7(1):104
Background
An available whole genome sequence for Aspergillus flavus provides the opportunity to characterize factors involved in pathogenicity and to elucidate the regulatory networks involved in aflatoxin biosynthesis. Functional analysis of genes within the genome is greatly facilitated by the ability to disrupt or mis-express target genes and then evaluate their result on the phenotype of the fungus. Large-scale functional analysis requires an efficient genetic transformation system and the ability to readily select transformants with altered expression, and usually requires generation of double (or multi) gene deletion strains or the use of prototrophic strains. However, dominant selectable markers, an efficient transformation system and an efficient screening system for transformants in A. flavus are absent. 相似文献17.
Melania D'Orazio Raffaella Scotti Laura Nicolini Laura Cervoni Giuseppe Rotilio Andrea Battistoni Roberta Gabbianelli 《BMC microbiology》2008,8(1):166
Background
Highly virulent enterohemorrhagic Escherichia coli O157:H7 strains possess three sodC genes encoding for periplasmic Cu, Zn superoxide dismutases: sodC, which is identical to the gene present in non-pathogenic E. coli strains, and sodC-F1 and sodC-F2, two nearly identical genes located within lambdoid prophage sequences. The significance of this apparent sodC redundancy in E. coli O157:H7 has not yet been investigated. 相似文献18.
David Šmajs Lenka Micenková Jan Šmarda Martin Vrba Alena Ševčíková Zuzana Vališová Vladana Woznicová 《BMC microbiology》2010,10(1):288
Background
Bacteriocin production is an important characteristic of E. coli strains of human origin. To date, 26 colicin and 9 microcin types have been analyzed on a molecular level allowing molecular detection of the corresponding genes. The production incidence of 29 bacteriocin types and E. coli phylogroups were tested in a set of 361 E. coli strains isolated from human urinary tract infections (UTI) and in 411 control strains isolated from feces of patients without bacterial gut infection. 相似文献19.
Background
Presence of all three ParaHox genes has been described in deuterostomes and lophotrochozoans, but to date one of these three genes, Xlox has not been reported from any ecdysozoan taxa and both Xlox and Gsx are absent in nematodes. There is evidence that the ParaHox genes were ancestrally a single chromosomal cluster. Colinear expression of the ParaHox genes in anterior, middle, and posterior tissues of several species studied so far suggest that these genes may be responsible for axial patterning of the digestive tract. So far, there are no data on expression of these genes in molluscs. 相似文献20.